It is possible that you could be pregnant if your period is three days late and you are experiencing fatigue and unusual discharge. While it's understandable to feel anxious about taking a pregnancy test, it is the most reliable way to confirm whether or not you are pregnant. The fear of seeing only one line can be overwhelming, but remember that a negative result does not necessarily mean you won't conceive in the future. If you're unsure about your boyfriend's sperm quality, it may be worth discussing with your healthcare provider to determine if any tests are necessary. In the meantime, try to stay positive and consider taking the test for peace of mind and clarity on your current situation.